A 39-storey skyscraper was evacuated amid earthquake fears after a group of martial arts enthusiasts caused the building to shake violently.

Just 17 Tae Bo fans were working out in the tower block's 12th floor gym but the vibrations they created were amplified by the building's structure causing panic and a mass evacuation of the floors above.

Prime Group, owners of the huge TechnoMart commercial-residential high-rise in Seoul, South Korea, said the group of middle-aged people had been working out to the pop song "The Power" by Snap when their movements set the upper floors of the tower shaking for 10 minutes.

Scientists sent in to investigate the tremors recreated the event in the 12th floor gym.

Chung Lan, a professor of architectural engineering at Dankook University, said: “We observed the vibrometer while performing the same kind of aerobic exercise that was performed at the time of the shaking which occurred on July 5.

“We noticed that the shaking was felt in the upper floors while the exercise was being performed while no other place showed signs of tremor.

“It just happens to be that the vibration cycle caused by Tae Bo collided with the vertical vibration cycle unique to the building.”

Chung was one of six professors from the Architectural Institute of Korea who inspected the building and recreated the Tae Bo exercise.